1. Field of the Invention
This application relates to solid calcium aluminate products for use in steel refining processes. More specifically, this invention relates to a calcium aluminate product that is manufactured from a liquid slag and a crushed material.
2. Background Information
Steel slags are a by-product of the steel refining process. In general, steel slags result from the process of separating impurities, such as sulfur, phosphorus and metal oxides from within the molten steel. A number of steel slags (e.g. furnace slags; ladle slags) are produced during the steel refining process. Basic Oxygen Furnace (BOF) and Electric Arc Furnace (EAF) slags are formed in a high temperature chemical process that incorporates the injection of high-pressure oxygen into a furnace that contains a mixture of molten metal, metal scrap, and a number of fluxes that typically include lime (CaO) and dolomitic lime (CaO.MgO). When in the furnace, the furnace slag is a liquid melt comprised of various sulfides and oxides that typically float on top of the molten steel because of the density differences between the molten steel and the molten liquid slag. After melting the scrap in the charge and bringing the carbon and temperature of the melt to the desired levels, the molten steel is tapped (poured) into a ladle while the furnace slag is retained in the furnace and subsequently tapped (poured) into a furnace slag pot.
While in the ladle, the molten steel can be subjected to additional refining processes (ladle refining processes). For instance, additional fluxes may be added to the molten steel in order to further remove impurities that remained within the molten steel after being tapped from the furnace. The slags that are formed during the ladle refining process are generally referred to as ladle slags. After the ladle refining process is complete, the refined molten steel is tapped (poured) into a continuous caster after which the ladle slags are poured into a ladle slag pot. Generally, the chemical composition, as well as the physical properties, of the ladle slag makes the ladle slag unsuitable for recycling into the steel refining process. Accordingly, most ladle slags are discarded and transported to landfills for disposal.